Replacing SiC substrates with the highest thermal conductivity material available, diamond (κ up to 2000 W/mK), will result in significantly lower thermal resistance AlGaN/GaN HEMTs. In this work we combine Raman thermography and thermal simulation to assess the thermal resistance of state-of-the-art GaN-ondiamond HEMTs. INTRODUCTION The RF output power density achievable for GaN-based high ele...

important aspect of computer design, with device performance being significantly affected by temperature. In addition, device lifetime can be decreased drastically because of large thermal stresses that occur especially at interfaces. The ability of a structure to remove heat is best quantified by its thermal resistance, which is given by the temperature difference divided by input power. In mi...

In this work, thermal transport in nanocrystalline materials is studied using large-scale equilibrium molecular dynamics simulation. Nanocrystalline materials with different grain sizes are studied to explore how and to what extent the size of nanograins affects the thermal conductivity and specific heat. Substantial thermal conductivity reduction is observed and the reduction is stronger for n...

This paper presents the study on the mechanism of heat transport in multilayer solid body with the assumption that the heat transfer proceeds with the aid of thermal conductivity. It presents a test conducted with lock-in thermography on multilayer structure with implanted defect. The structure is made from materials of different thermal conductivity k. Different layers of tested structure desc...

Thermal transport measurements in multi-wall carbon nanotube (MWCNT) bundles at elevated temperatures up to 830 K are reported using a novel generalized electrothermal technique. Compared with individual CNTs, the thermal conductivity (k) of MWCNT bundles is two to three orders of magnitude lower, suggesting the thermal transport in MWCNT bundles is dominated by the tube-to-tube thermal contact...

Electrowetting (EW)-induced droplet motion has been studied over the last decade in view of its promising applications in the field of microfluidics. The objective of the present work is to analyze the physics underlying two specific EW-based applications for microelectronics thermal management. The first of these involves heat absorption by liquid droplets moving on the surface of a chip under...

The main objective of the work reported here is to assess factors that could affect the outcome of a proposed open flame test for barrier fabrics (BF-open flame test). The BF-open flame test characterizes barrier effectiveness by monitoring the ignition of a flexible polyurethane foam (FPUF) layer placed in contact with the upper side of the barrier fabric, exposed to a burner flame from below....

REBCO coated conductors (CCs) have the potential to widen considerably the application areas of superconductivity. Quench protection of REBCO-based devices represents one of the major obstacles to this expansion. Thermal conductivity data are mandatory ingredients for quench simulation studies. In particular, the transverse thermal conductivity (kT) of the CC plays a key role in case of quenche...

A new structure thermal vacuum sensor with two pn junction diodes, Th-A and Th-B, as a high sensitive temperature sensor working like a thermistor and a micro heater formed on a micro air‒bridge is proposed. The micro air‒bridge is separated into two regions of A and B. The Th-A measures the temperature of the micro-heater formed on the region A and the Th-B does that of the region B which is c...

S. Bruce, A. Trasser, M. Birk, A. Rydberg and H. Schumacher. Uppsala University, Box 534, S-751 21 Uppsala, Sweden. University of Ulm, Abt. EBS, D-89069 Ulm, Germany. Abstract A novel method for finding the thermal time constant of HBTs is proposed. It utilizes small signal measurements in the frequency domain of the typical negative differential resistance found in the active region, i.e., nor...